The green bond market is emerging as an impactful financing mechanism in climate change mitigation efforts. The effectiveness of the financial market for this transition to a low-carbon economy depends on attracting investors and removing financial market roadblocks. This paper investigates the differential bond performance of green vs non-green bonds with (1) a dynamic portfolio model that integrates negative as well as positive externality effects and via (2) econometric analyses of aggregate green bond and corporate energy time-series indices; as well as a cross-sectional set of individual bonds issued between 1 January 2017, and 1 October 2020. The asset pricing model demonstrates that, in the long-run, the positive externalities of green bonds benefit the economy through positive social returns. We use a deterministic and a stochastic version of the dynamic portfolio approach to obtain model-driven results and evaluate those through our empirical evidence using harmonic estimations. The econometric analysis of this study focuses on volatility and the risk–return performance (Sharpe ratio) of green and non-green bonds, and extends recent econometric studies that focused on yield differentials of green and non-green bonds. A modified Sharpe ratio analysis, cross-sectional methods, harmonic estimations, bond pairing estimations, as well as regression tree methodology, indicate that green bonds tend to show lower volatility and deliver superior Sharpe ratios (while the evidence for green premia is mixed). As a result, green bond investment can protect investors and portfolios from oil price and business cycle fluctuations, and stabilize portfolio returns and volatility. Policymakers are encouraged to make use of the financial benefits of green instruments and increase the financial flows towards sustainable economic activities to accelerate a low-carbon transition.

Duncker & Humblot - Berlin. Ein Forum für die Wissenschaft seit 1798

European governments are struggling to regain economic strength in the coronavirus pandemic as in many countries the number of new infections seems to gradually subside. Growth rates deep in the red call for a reconstruction programme when the crisis is finally manageable and economic activity can resume. Amidst this, there are again influential groups that claim “this is not the time to insist on strict climate protection goals”. On the contrary, the ongoing COVID-19 crisis has clearly illustrated what climate disasters, often occurring locally, could do to the life of citizens. The reconstruction programme needs to initiate the great green transition. The transformation from a climate-distorting to a climate-protecting economy opens up investment opportunities and points to financing needs comparable with those necessary for the rebuilding of the European economy after World War II. The great green transition is a unique chance to pursue policies for a new and sustainable growth regime.

We develop a theoretical model that features a business cycle‐dependent relation between output, price inflation and inflation expectations, augmenting the model by Svensson (1997) with a nonlinear Phillips curve that reflects the rationale underlying the capacity constraint theory (Macklem, 1997). The theoretical model motivates our empirical assessment, based on a regime‐switching Phillips curve and a regime‐switching monetary structural VAR, employing different filter‐based, semi‐structural model‐based and Bayesian factor model‐implied output gaps. The analysis confirms the presence of a convex relationship between inflation and the output gap, meaning that the coefficient in the Phillips curve on the output gap recurringly increases during times of expansion and abates during recessions. Sign‐restricted monetary policy shocks based on a regime‐switching monetary SVAR reveal that expansionary monetary policy induces less pressure on inflation at times of weak as opposed to strong growth; thereby rationalizing relatively stronger expansionary policy, including unconventional volume‐based policy, during times of deep recession. A further augmented model shows that an effective euro exchange rate shock, too, implies business cycle state‐dependent responses, with more upward pressure on prices arising from unexpected currency depreciation at times of expansion than during recession phases.